trachsler



F. A. TRACHSLER LOCK GUARD Original Filed April 24. 1950 Feb. 21, 1956 INVENTOR. F7950 A. Rae/ $451 BY nrv-oeuzvs.

United States Patent Ofifice LOCK GUARD Fred A. Trachsler, Vallejo, Calif.

Original application April 24, 1950, Serial No. 157,715, now Patent No. 2,631,881, dated March 17, 1953. Divided and this application October 21, 1952, Serial No. 315,969

3 Claims. (Cl. 292346) locked doors by means of a sheet of thin material such as isinglass, Celluloid or the like by slipping the sheet between the jamb and door and against a cam-type lock bolt in order to force the bolt open and thus release the lock to obtain entry. The present invention provides a means to prevent the use of such an implement to effect opening of locked doors and the same is an object of this invention.

Another object is to provide apparatus for the prevention of opening of locked closures by means of an improved strike plate normally afl'ixed to the door jamb.

Further objects of the present invention are to provide improved hardware for locking mechanisms for the purposes above set forth and which is inexpensive and simple to manufacture and install and which will not interfere with the normal operation of the closures and which effectively prevents unlawful and undesired opening of locked closures.

Further objects of the present invention will become apparent upon reading the following specification and referring to the accompanying drawings in which similar characters of reference represent corresponding parts in each of the several views.

In the drawings:

Fig. 1 is a perspective view of a fragmentary part of a closure jamb equipped with the present invention.

Fig. 2 is a horizontal sectional view of a door and jamb equipped with the present invention and showing a sheet of thin material, such as Celluloid, trapped in the guard.

Fig. 3 is a front elevation of the lock guard.

Fig. 4 is an end elevation thereof.

As illustrated and described herein, the present invention is arranged to be attached to a conventional door jamb and is useable with conventional lock hardware particularly wherein the bolt of the lock is provided with a cam face. It will be understood, however, that the guard might with equal facility be carried by the door rather than the jamb.

The device is illustrated in Figs. 1 through 4 and com- 2,735,711 Patented Feb. 21, 1956 prises a plate, such as a strike plate B, carried by a door jamb C provided with an aperture 2 to receive a lock bolt D which is indicated as provided with a cam face 4. The bolt is carried by a door A. The jamb C, as illusand 1.4, with a recess 16 therebetween. The strike plate, having a marginal bifurcation at top, bottom and rear, may be atfixed to the jamb so that the rear bifurcation is adjacent to the stop E. The groove or recess 16 extends continuously in a U-shaped fashion around the strike plate and surrounds the bolt-receiving aperture 2. The flange 13 is larger than the flange 14 which lies against the jamb C.

Fig. 2 illustrates a jimmy sheet G formed of Celluloid It is noted that the flange 14, lying against the jamb, is less than the width of flange 13 and thus the sheet G is trapped between flange 13 and flange 14 in the recess 16 or between flange 13 and the jamb.

The invention has been illustrated and described in specific detail of use and installation for purposes of clarity of understanding and it is intended that various 2. A guard according to claim 1 in which the edge of said guard is grooved at top and bottom similar to the groove on its side edge.

3. A guard according to claim 2 wherein the flange nearest said door is wider than the flange nearest said jamb.

References Cited in the file of this patent UNITED STATES PATENTS 975,675 Bumiller Nov. 15, 1910 1,091,453 Fletcher Mar. 24, 1914 1,727,323 Bartlett Sept. 10, 1929 1,844,459 Brandon Feb. 9, 1932 2,631,881 Trachsler M81. 17, 1953 

